A substrate processing apparatus is used to apply a variety of processing to substrates such as semiconductor substrates, substrates for use in liquid crystal displays, plasma displays, optical disks, magnetic disks, magneto-optical disks, photomasks, and other substrates. Such a substrate processing apparatus typically applies a plurality of successive processing to a single substrate.
The substrate processing apparatus as described in JP 2003-324139 A includes an indexer block, an anti-reflection film processing block, a resist film processing block, a development processing block, and an interface block. An exposure device is arranged adjacent to the interface block as an external device separate from the substrate processing apparatus.
The indexer block takes out a substrate from a cassette for storing substrates in multiple stages and stores a substrate into the cassette, and the anti-reflection film processing block forms an anti-reflection film under a photoresist film to reduce possible standing waves and halation generated during exposure processing.
The resist film processing block forms the photoresist film on the anti-reflection film, and the development processing block applies development processing to the substrate after exposure processing. Specifically, this development processing block includes a development processing group that applies the development processing to the substrate after the exposure processing and an after-mentioned thermal processing group for development that applies thermal processing to the substrate related to that development processing.
In the above-described substrate processing apparatus, a substrate is carried from the indexer block into the anti-reflection film processing block and the resist film processing block, where the formation of an anti-reflection film and resist film coating processing are applied to the substrate respectively. The substrate is then transported to the exposure device through the interface block.
After exposure processing has been applied to the resist film on the substrate by this exposure device, the substrate is transported to the development processing block through the interface block. In the development processing block, development processing is applied to the resist film on the substrate to form a resist pattern thereon, and the substrate is subsequently carried into the indexer block.
With recent improvements in the density and integration of devices, making finer resist patterns have become very important. Conventional exposure devices typically perform exposure processing by providing reduction projection of a reticle pattern on a substrate through a projection lens.
With the conventional exposure devices, however, the line width of an exposure pattern is determined by the wavelength of the light source of an exposure device, thus making it impossible to make a resist pattern finer than that.
For this reason, a liquid immersion method is suggested as a projection exposure method allowing for finer exposure patterns (refer to, e.g., WO99/49504 pamphlet). In the projection exposure device according to the WO99/49504 pamphlet, a liquid is filled between a projection optical system and a substrate, resulting in a shorter wavelength of exposure light on a main surface of the substrate. This allows for a finer exposure pattern.
With respect to the above-described conventional exposure device, however, since the exposure processing is performed with the substrate in contact with a liquid, the substrate with the liquid adhering is carried from the exposure device. As a result, the liquid adhering to the substrate carried out of the exposure device may drop in the substrate processing apparatus, causing operational troubles such as abnormalities in the electric system of the substrate processing apparatus.